The repeatability standard deviations are pooled over the K
occasions to obtain an estimate with K(J - 1) degrees of
freedom of the level-1 standard deviation
$${\large s}_1 = \sqrt{\frac{1}{K} \sum_{k=1}^{K} {\large s}_k^2} \,\,\,\, . $$
Note: The same notation is used for the repeatability standard deviation
whether it is based on one set of measurements or pooled over several
sets.

Database

The individual short-term standard deviations along with
identifications for all significant factors are recorded
in a file. The best way to record this information is by using
one file with one line (row in a spreadsheet) of information
in fixed fields for each group. A list of typical entries follows.